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Large Assembly Stability

Question asked by Allen Ondes on Nov 4, 2009
Latest reply on Nov 11, 2009 by Allen Ondes
  How much impact does the file structure of large assemblies (and the sub-assemblies/parts) contribute to stability of a very large assembly?  Let me better define what I mean by file structure.  We see several issues with CAD files downloaded typically from OEM (and others).  These issues, when taken in part files or small assemblies are fairly easily handled by SW.  However, take many many of these small issues and load all of these into one very large assembly file … on the order of >500 parts and 1GB assembly file.  Now the functional stability of SW becomes an issue.  My contention is improving the contents of the part/assembly files within this large assembly will greatly increase the file’s stability. The typically issues we see are: 1)Using OEM assemblies defined by externally referenced parts … in which the parts are externally referencing the assembly.  What came first the part or the assembly?  See SMC’s attached image of NCDJPB6-025D  2) Using assemblies/parts with extremely large exported multi-body surfaces.  3800 surfaces for a camera part file, creating a 20Mb file for a part that should be 500Kb.  3)Using exported CAD files (iges, step, parasolid, etc) in less than compatible formats.  Not all formats are created equal.  These formats have limited functionality in a SW file: section view, drawing creation, mass analysis, transparency, etc.  4) Overly complex, multi-body part files for simple hardware items.  Typically these items are not accurate models … threads are never model accurately.      In conclusion - these issues converge to … when and how do you decide to re-model (redraw) CAD files.  Do you insert any and every type of CAD model?  Or do you set-up guidelines for recreating the CAD files?  Recreate to improve stability … Time consumed versus stability …